The present invention relates to a ring clamp system for securing heating, ventilating, and air conditioning (HVAC) ductwork components. More particularly, it relates to a ring clamp of the system having an adjustable band defining removably interlocking projections.
Air handling systems, such as HVAC systems, include various ductwork components employed to direct heated, or cooled, and/or filtered air from a source to one or more locations, for example, a building or a room. The air handling systems can be employed in residential, commercial, and/or industrial buildings. Specifically, the air handling system can include a heating system (for example, a furnace and a blower), a cooling system (for example, an air conditioning unit), and/or a filtering system (for example, an air blower and one or more filter components). Regardless of the manner in which air is handled or treated, the ductwork components direct the treated air, in concert with an air movement system, to the location of interest. The air movement system can include one or more fans, or one or more blowers. The ductwork components can include one or more of a plenum (e.g., a hot air plenum, a cold air plenum, a straight plenum, a plenum with furnace take-off), hot air take-offs, ducts, pipes (straight or bent), boots, wall stacks, registers (e.g., wall or floor registers), tees, reducers, etc. (hereinafter collectively referred to as “ductwork components”). In this regard, ductwork components can generally be constructed of either pliant metals or rigid plastics. The pliant metal ductwork components are characterized by a level of flexibility that can be manipulated, for example by a metalworker, in joining the components together. To this end, pliant metal ductwork components are often attached with duct tape. In contrast, rigid plastic ductwork components are characterized as generally inflexible, thereby necessitating careful alignment and high-strength attachment.
More recently, a unique ductwork component design has been devised whereby the ductwork components are foam-based and integrally formed. Although not limited to the assembly and attachment of rigid plastic ductwork components, the present invention is particularly useful in coupling integrally formed, foam-based components that provide structural strength and airflow handling capability without having a separate metal layer. Such ductwork components are described in U.S. patent application Ser. No. 10/252,032, which is incorporated herein by reference.
Coupling of the integrally formed, foam-based ductwork components presents various obstacles. For example, each installation is different, thus necessitating that a variety of ductwork components be utilized. Therefore, for each installation, the ductwork components will likely be attached in varying sequences. Naturally, this complicates the installation, translating to more time spent on the job, which relates to a more costly installation. Additionally, as with any installation, an airtight seal between ductwork components is of primary importance.
Regardless of the construction of the ductwork components, the prior art has approached these challenges by employing tapes and adhesive sealants, and/or a variety of clamps requiring the use of multiple tools. In this regard, the use of the tapes and adhesives is both time-consuming and costly, and for this reason, shortcuts are sometimes taken to the detriment of the quality of the seal at the junction. The clamps employed in the prior art are often metallic and require the use of a variety of tools. For example, a common clamp is a hose clamp style of device having a threaded bolt. Screwdrivers or wrenches are typically employed to turn the bolt. Movement of the threaded bolt draws the clamp together. In this regard, the clamp is only as strong as the threads on the bolt, and for this reason, clamps in the style of hose clamps can lack sufficient clamping force to secure the rigid ductwork components of the integrally formed, foam-based construction. To this end, the failure to achieve a high quality seal between ductwork components can lead to blow-by of the air forced through the air handling system, which in turn can introduce dust, mold, or bacteria into the local residential, commercial or industrial environment.
Apart from the unique challenges inherent in coupling integrally formed, foam-based ductwork components, the prior art has struggled to achieve convenient and effective coupling between the common (galvanized and/or flexible) ductwork components. For example, U.S. Pat. No. 5,095,945 to Murphy describes a plastic self-insulating ductwork system employing a drawband secured to an annular groove formed in an adapter conduit. The drawband described in Murphy is difficult to manipulate due to its small size, and relies upon the annular groove in the adapter conduit to affect a seal. It is known in the art that such annular grooves occasionally fail to achieve a high quality seal between ductwork components. To this end, Murphy also describes adaptor conduits having slotted, spring-like teeth. In this regard, Murphy teaches the use of adhesives to seal the components together. Therefore, the prior art does not offer convenient and effective ductwork attachment mechanisms for common components, much less the more advanced integrally formed, foam-based ductwork components.
HVAC air handling systems employing ductwork components are useful and popularly employed in residential, commercial, and industrial settings. In particular, HVAC systems employing integrally formed, foam-based ductwork components offer many advantages over conventional, metallic ducts. Unfortunately, the integrally formed, foam-based ductwork components present unique assembly challenges. Therefore, a need exists for a convenient and effective method of assembling integrally formed, foam-based HVAC ductwork components.